LazyInitializationException Hibernate Spring Help!!!

[duardito]

Perhaps what you are trying to say is that there should only be one overall transaction in the controller?

sorry if I didn't answer correctly before, I want to say something like this:

you have your controller:

class controller{
public ModelAndView onSubmit(Object command){
method A (propagation=Propagation.REQUIRED)
method B (propagation=Propagation.REQUIRED)
method C (parameter mehotd A, parameter method B)(propagation=Propagation.REQUIRED) 
// here LazyInitializationException because transaction of each method are closed, because
ModelAndView onSubmit(Object command) is not transactional
}
}

one solution to this would be something like this:

class DAO{
propagation=Propagation.REQUIRED
method TOCONTROLLER{
method A (propagation=Propagation.REQUIRED)
method B (propagation=Propagation.REQUIRED)
method C (parameter mehotd A, parameter method B)(propagation=Propagation.REQUIRED) 
//here you will not have exception because parent's method is transactional and required, so this is a transaction over other transactions included in sub_methods
}
}

IMHO.

what dou you think?

[logixplayer]

Category controller is calling my category service.
Category Service is defined as such:

	@Transactional(propagation=Propagation.REQUIRED, readOnly=true)
	public List<Category> findByName(Object name, int[] rowStartIdxAndCount){
		 List<Category> result = iCategoryDAO.findByName(name,rowStartIdxAndCount);
		return result;
	}

So it is defined as
1)@Transactional
2)propagation=Propagation.REQUIRED
3)readOnly=true

Now, after I get back the List of Categories, I do this:

Set<Category> subCategories = category.getCategories();

and this is when I get the lazyLoadException.
Once again, my getCategories method is declared as LAZY:

	@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "category")
	public Set<Category> getCategories() {
		return this.categories;
	}

Essentially this exception is happening outside of the first transaction (to get categories). I thought that by using OpenEntityManagerInViewFilter it can somehow re-open/re-attach that original session ....

web.xml:

	<filter>
	    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
	    <filter-class>
	        org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
	    </filter-class>
	      <init-param>
			<param-name>singleSession</param-name>
			<param-value>false</param-value>
		</init-param>
	    
	</filter>
	
	<filter-mapping>
	    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
	    <url-pattern>/*</url-pattern>
	</filter-mapping>

Any thoughts?

[duardito]

here is your problematic code:

		List<Category> categories = categoryService.findByName("Autos", null);//here session is opened
		//	should only be one category in actuality
		for (Category category : categories) {
			System.out.println("category: "+category.getName());//here session is closed
			
Set<Category> subCategories = category.getCategories(); LAZY EXCEPTION HERE because youe session is closed

to solve this you must decouple your dao code from controller, because as I said before your method is not transactional

public ModelAndView onSubmit(Object command)

so your option is to do a dao method doing all this;

@Transactional
class DAO{

@Transactional(propagation=Propagation.REQUIRED, readOnly=true)
public Set returnSet(){

List<Category> categories = categoryService.findByName("Autos", null);
		
	for (Category category : categories) {
			
Set<Category> subCategories = category.getCategories();
return subCategories ;
}
}

with this method you will be sure your returnSet() transaction will overwrite inner transactions, and then in your Controller class you can call this method without exception.

finally your controller class would be like:

public class CategoryController extends SimpleFormController {

	public ModelAndView onSubmit(Object command) throws ServletException {
		CategoryBean categoryBean = (CategoryBean) command;
		System.out.println("the name from the command bean is: "+categoryBean.getName());
		
		ICategoryService categoryService = (ICategoryService)DataAccessServiceFactory.getBean("iCategoryService");
		ITopicService topicService = (ITopicService)DataAccessServiceFactory.getBean("iTopicService");
			
Set<Category> subCategories = returnSet(); //CODE CHANGED
			for (Category subCategory : subCategories) {
				System.out.println("subCategory: "+subCategory.getName());
				//Set<Topic> topics = subCategory.getTopics();
				List<Topic> topics = topicService.findByCategoryID(subCategory.getCategoryId(), null);
				System.out.println("****now to get topics if there are any!****");
				for (Topic topic : topics) {
					System.out.println("topic: "+topic.getTitle());
					System.out.println("****now to get submissions if there are any!****");
					Set<Submission> submissions = topic.getSubmissions();
					for (Submission submission : submissions) {
						System.out.println("submission topic: " +submission.getTopic());
						System.out.println("submission title: " +submission.getTitle());
					}
				}
			}

what do you think?

[duardito]

now I see other think, maybe you will have same problem with other code like this, because you are doing the same.

List<Topic> topics = topicService.findByCategoryID(subCategory.getCategoryId(), null);
				System.out.println("****now to get topics if there are any!****");
				for (Topic topic : topics) {
					System.out.println("topic: "+topic.getTitle());
					System.out.println("****now to get submissions if there are any!****");
					Set<Submission> submissions = topic.getSubmissions();

[logixplayer]

Appreciate the reply but that's really not the way I want to go.
The solution you posted is really not very flexible and it totally defeats the purpose of LazyLoading.

I would like to lazy load when I need to, which is why there is a OpenEntityManagerInViewFilter in the first place.


Note the following definition of OpenEntityManagerInViewFilter:

Servlet 2.3 Filter that binds a JPA EntityManager to the thread for the entire processing of the request. Intended for the "Open EntityManager in View" pattern, i.e. to allow for lazy loading in web views despite the original transactions already being completed.

The definition is perfect. It allows lazy loading in web views despite the original transactions already being completed.
But it's still not working. Some configuration missing somewhere!!!

Thoughts and solutions? Thanks!

[duardito]

ok, good luck.

[duardito]

I have seen one thing, in docs I have seen this:

http://static.springsource.org/sprin...iewFilter.html

Servlet 2.3 Filter that binds a Hibernate Session to the thread .....

what version of servlet are you using?

and I have seen some spanish and portuguese posts talking about this, and they had similiar problem , solving it changing order of OpenEntityManagerInViewFilter inside web.xml putting it first, and then other delcarations.

[logixplayer]

I have seen one thing, in docs I have seen this:

http://static.springsource.org/sprin...iewFilter.html

Servlet 2.3 Filter that binds a Hibernate Session to the thread .....

what version of servlet are you using?

and I have seen some spanish and portuguese posts talking about this, and they had similiar problem , solving it changing order of OpenEntityManagerInViewFilter inside web.xml putting it first, and then other delcarations.

Yes I also indicated this in my previous posts,
I noticed it said servlet 2.3 as well which made me go hmmmm.
I am using Servlet 2.5 and JSP 2.1.
Is this a problem?
I also took the advice of others and have made the OpenEntityManagerInViewFilter the very first thing in my web.xml, observe:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
	xmlns="http://java.sun.com/xml/ns/javaee" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  
     <!-- Include this if you are using Hibernate -->
	<filter>
	    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
	    <filter-class>
	        org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
	    </filter-class>
	      <init-param>
			<param-name>singleSession</param-name>
			<param-value>false</param-value>
		</init-param>
	    
	</filter>
	
	<filter-mapping>
	    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
	    <url-pattern>/*</url-pattern>
	</filter-mapping>
	
  	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>
					<!-- classpath:applicationContext.xml  -->
					<!-- classpath:/data-access-context.xml  -->
					classpath:data-access-context.xml
		</param-value>
	</context-param>
  
	<welcome-file-list>
	  <welcome-file>/WEB-INF/jsp/index.jsp</welcome-file>
	</welcome-file-list>

    <!-- Spring MVC Configuration -->
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>
            org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
        <load-on-startup>2</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>*.html</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>*.person</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>*.tribute</url-pattern>
    </servlet-mapping>
    
	<jsp-config>
	    <taglib>
	      <taglib-uri>/spring</taglib-uri>
	      <taglib-location>/WEB-INF/spring-form.tld</taglib-location>
	    </taglib>
	</jsp-config>
</web-app>

Any thoughts or ideas? Thanks a lot.

[duardito]

look last post.

https://forum.hibernate.org/viewtopic.php?f=1&t=986390

[logixplayer]

look last post.

https://forum.hibernate.org/viewtopic.php?f=1&t=986390

Hi, I from that post, I tried this:

	<filter-mapping>
	    <filter-name>OpenEntityManagerInViewFilter</filter-name>
	    
            <servlet-name>dispatcher</servlet-name> 
	</filter-mapping>

instead of using <url-pattern>/*</url-pattern> because dispatcher is my spring servlet.

    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>
            org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
        <load-on-startup>2</load-on-startup>
    </servlet>

but it didn't work. So I reverted back...
still stuck...